(R)-(+)-Nicotine - statistical evaluation (t-test) revealed that the subjects were able to identify R(+)- and S(-)-nicotine at olfactory and trigeminal concentrations...At concentrations near the detection thresholds, i.e., clearly below subjective pain thresholds, smokers rated both nicotine stereoisomers to be significantly more pleasant than did nonsmokers... (Hummel et al., 1992) Subjects were able to discriminate between the two stereoisomers of nicotine. Whereas both groups reported the R( +) isomere to cause an unpleasant sensation, the S(-) isomere was perceived as pleasant by smokers, but not by non-smokers Human subjects can discriminate qualitatively betweenthe S-(-) and the R-(-) stereoisomers of nicotine, although the relative importance of olfactory and trigeminal inputs in this discriminative ability is unclear (Walker et al., 1996)  Ref: Thuerauf, Norbert; Kaegler, Michael; Renner, Bertold; Barocka, Arnd ; Kobal, Gerd, Specific Sensory Detection, Discrimination, and Hedonic Estimation of Nicotine Enantiomers in Smokers and Nonsmokers: Are There Limitations in Replacing the Sensory Components of Nicotine?, Journal of Clinical Psychopharmacology. 20(4):472-478, August 2000; T. Hummel, C. Humme1, E. Pauli and G. Kobal, Olfactory discrimination of nicotine-enantiomers by smokers and mom-smokers, ChemicaJ Senses, Vol. 17(5), 13-21, 1992; James C. Walker, Martin Kendal-Reed, C. Jane Keiger, Merouane Bencherif, Wayne L. Silver, Olfactory and trigeminal responses to nicotine, Drug Development Research, Volume 38, Issue 3-4, Date: July - August 1996, Pages: 160-168.

(S)-(-)-Nicotine - statistical evaluation (t-test) revealed that the subjects were able to identify R(+)- and S(-)-nicotine at olfactory and trigeminal concentrations...At concentrations near the detection thresholds, i.e., clearly below subjective pain thresholds, smokers rated both nicotine stereoisomers to be significantly more pleasant than did nonsmokers... (Hummel et al., 1992) Subjects were able to discriminate between the two stereoisomers of nicotine. Whereas both groups reported the R( +) isomere to cause an unpleasant sensation, the S(-) isomere was perceived as pleasant by smokers, but not by non-smokers Human subjects can discriminate qualitatively betweenthe S-(-) and the R-(-) stereoisomers of nicotine, although the relative importance of olfactory and trigeminal inputs in this discriminative ability is unclear (Walker et al., 1996)  Ref: Thuerauf, Norbert; Kaegler, Michael; Renner, Bertold; Barocka, Arnd ; Kobal, Gerd, Specific Sensory Detection, Discrimination, and Hedonic Estimation of Nicotine Enantiomers in Smokers and Nonsmokers: Are There Limitations in Replacing the Sensory Components of Nicotine?, Journal of Clinical Psychopharmacology. 20(4):472-478, August 2000; T. Hummel, C. Humme1, E. Pauli and G. Kobal, Olfactory discrimination of nicotine-enantiomers by smokers and mom-smokers, ChemicaJ Senses, Vol. 17(5), 13-21, 1992; James C. Walker, Martin Kendal-Reed, C. Jane Keiger, Merouane Bencherif, Wayne L. Silver, Olfactory and trigeminal responses to nicotine, Drug Development Research, Volume 38, Issue 3-4, Date: July - August 1996, Pages: 160-168.

Ionones, Irones, Damascones & Structurally Related Odorants

Acyclics (Alcohols, Esters, Acids, Aldehydes)

Lactones

Sesquiterpenoid Related Odorants